Electric motors are used in many industries. On automobiles, motors are used in various locations. For example, motors may be used to drive a pump.
Commonly, these motors generally comprise two main components; a motor assembly and a drive assembly. The motor assembly includes the actual rotating motor. The drive assembly includes the drive electronics for controlling the operation of the motor. Commonly, the motor and the drive assembly are two separate components connected by an external cable assembly. There are several disadvantages to a separate drive assembly and motor assembly.
One disadvantage of a separate motor assembly is the external cable assembly. An external cable assembly increases electrical resistance for the system, and may act as an antenna which may both receive and radiate unwanted electromagnetic interference. In fact, the FCC has regulated the electromagnetic radiation emitted from a motor. To prevent electromagnetic interference, a more expensive shielded wire must be used if electromagnetic interference exceeds the FCC regulation.
Another disadvantage to providing a separate drive assembly and motor assembly is the integration of the two separate units into the finished product. Having two separate assemblies increases the space required for a motor and drive unit. Also, the assembly complexity for mounting two components is relatively high.
For automotive applications, motors use a relatively low voltage and draw high currents. This causes the motors to dissipate more power. Some industrial integrated drive motors operate at 110 volts. The high voltage motors draw little current and dissipate small amounts of power. Because of the low power dissipation, organic-based circuit boards for power distribution may be used in such applications. However, in low voltage automotive applications, organic-based circuit boards cannot be used.